The VS Ribozyme catalyzes the same self-cleavage reaction as the hammerhead, hairpin and hepatitis delta virus ribozymes, however differs in sequence and secondary structure from these and all known ribozymes. This suggest that the RNA structure involved in the cleavage reaction of the VS Ribozyme may be different from those of other catalytic RNAs. While at present time there is limited information available on the structure and function of the VS ribozyme, generating an artificial phylogeny for the ribozyme would prove useful in probing the structural and functional properties of this ribozyme. Through an in vitro selection assay we hope not only to define an artificial phylogeny for the ribozyme, but also to select for a variant of the VS Ribozyme that is capable of at least 15 percent ligation efficiency for use in NAIM/NAIS experiments.